Monday, 17 June 2013

Hairy Caterpillars

Japanese poisonous caterpillars
Cute, right?
Last year I mentioned 毛虫 in the orientation lecture I did for the ALTs coming into my prefecture. It was part of a section on annoyances and dangers, and I told them all to stay away from the hairy caterpillars. I’d never seen one, so it was pretty hypothetical. In English 毛虫 seems to translate as either Pine Processionary Caterpillars or Oak Processionary Caterpillars (closely related).

Fast forward to last week, and the hedge beside my carport was crawling with the cute but scary little buggers  (sorry, I can’t resist EVERY pun!).
Caterpillars too close to motorcycle
Forgive the blur, I was in a hurry to get away from them... but see how close they are to my bike?!
At first I thought that they wouldn’t be an issue if we stayed away from them and didn’t provoke their defensive mechanism. I started to get more worried after the vice principal at one of my schools told me to stop parking Rothbart under the trees because 毛虫 might fall on the seat. He said that if they left hairs on the seat and I sat on in, the effects would hit me while I was on the road and “terrible things will happen”. I didn’t know they could penetrate clothing. Then the next day at another school, the garden area was closed off with a big “Danger! 毛虫!” sign and exterminators were called in.
They were everywhere
“Right” I thought, “I need to refresh myself on what the deal is with these guys.” I did a quick google and found story after story of dogs dying in Spain and Portugal after getting the hairs in their mouths and throats. It sends the tongue narcotic and closes the airways. The man person suggested that the European ones might be more dangerous, but the pictures looked the same.

Happy looking hairy caterpillar on motorbike seat
So little, but I hear that terrible things will happen
Then I found one on my bike seat, and the same day a whole bunch of them started having a little procession (processing? processionaling?) across the front door. I went out and bought some pesticide.

My decision may have come too late for this poor bush, sadly
Good bye, hairy little caterpillars.
Can anyone tell me, are the Japanese ones REALLY that dangerous?   
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  1. Saw this on toxic caterpillars. Use non-toxic castile soap mixed in water as an insect repellent in organic garden; it works on everything. Also use orange oil mixed in water to repel ants; which works:

    1. Thank you, that sounds really useful. I just planted a small garden and it is already getting destroyed by insects but I don't want to use any chemicals that could hurt my dogs or the birds who eat the insects.

  2. Thanks for the heads up. I haven't seen one, but I'm sure Tsukahara has them. This place seems to have every creepy, crawly insect known. In the fall, they have these really cool glow in the dark wormy things. I believe they are immature fire flies.

    1. Does that mean you have lots of fireflies around this time of year? It sounds idyllic, I hope we get a chance to come visit you soon!

    2. Not just for the fireflies, of course!

  3. I heard that Kawanishi puts on quite a show of lights. Ajimu also has quite a few fireflies. Tsukahara has some lights, but they hang out near the river. The firefly larvae seem to be everywhere in the fall. It's fun to walk the dogs in the late evening and look for glow in the dark wormy things. It makes me feel like a kid again.


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